Tenpin.



E. G. LSON.

Patented Feb. 24, 1914,

AA p 7 i UNITED STATES PATENT OFFICE.

EDGAR G. WILLSON, OF APPLE'I'ON, WISCONSIN.

TENPIN.

To all echo-m it may concern:

Be it known that I, EDGAR G.NV1LLsoN, a citizen of the United States, and resident of Appleton. in the county of Outagamle and State of Visconsin, have invented new and useful Improvements in Tenpins, of which the following is a description, reference being had to the accompanying drawings, which are a part of this specification.

This invention has for its object to provide a tenpin which is permanently symmetrical in shape and unvarying in its weight and not liable to breakage from the rough treatment to which it is ordinarily subjected.

A tenpin in order to have the desirable resonance and life when struck must be constructed of hard wood such as maple and the usual practice has been to turn them out of av single piece of maple. The diameter at the largest part is such that it is impossible to thoroughly kiln dry the stock without killing the fiber and deadening the pin. Attempts to kiln dry the stock from which tenpins are made to an extent that would affect the center of the pin have resulted in rendering the pin liable to breakage at the neck portion thereof on account of the fiber being parched or deadened. It is found to be practically impossible to thoroughly kiln dry hard wood of five inches diameter, which is approXimately the diameter of the pin, on account of the casehardening effect or the drying out and closing of the pores of the wood at the surface preventing the escape of moisture from the central portion and consequently tenpins are usually only partially kiln dried and contain considerable moisture,which in time escapes by the air dry ing process. Though the pin may have been turned perfectly true and symmetrical in accordance with regulation requirements at the time it was made, it soon begins to shrink and lose weight, the individual members of a set sometimes. varying in weight from two to twelve ounces by the time the pins are sold though they have been accurately adjusted as to weight at the time they were made. Besides affecting the weight of the pins more-or less according to the density of grain of the wood, this drying out of the pin after it is turned up causes a warping or distortion in shape, for that portion of the wood which was Specification of Letters Patent.

Application filed October 20, 1913.

Patented Feb. 24, 1914. Serial No. 796.148.

tion than in another, for its symmetry has been destroyed. Not only this, but the warping or distortion of the pin through air drying sets up a state of tension within the pin which frequently causes the pin to split when it is hit a hard blow at the right part of its edge grain. Heretofore the only remedy for these defects has been a thorough air drying of the stock before the pin is turned. As this usually requires about two years for properly aging the wood it is obviously an expensive-and difii cult method for commercial use.

The present invention contemplates the use of wooden strips of such thickness that kiln drying'may be used without deadening its fiber, the pin being built up of a number of such strips firmly secured together and arranged in such a manner that the edge grain is no where exposed to the direct blow when the pin is struck but that instead'a belt is formed around the pin of slabs presenting their slash grain to the blow of the ball or other pins.

With the above and other objects in view the invention consists in the'tenpin as'herein claimed and all equivalents.

Referring to the accompanying drawings in which like characters of reference indicate the same parts in the different views: Figure ,1 is an elevation of a tenpin con structed in accordance with this invention; Fig. 2 is a longitudinal sectional view therethrough: Fig. 3 is a transverse sectional view therethrough; and, Fig. 4 is a similar view of a slightly modified form of "the invention.

- In these drawings 10 indicates a pair of central or core strips which may be preferably about one and two-thirds inches thick which will permit of their being thoroughly kiln dried before use. These two strips are glued together to form a central core approximately square in cross section, the diagonal of the square cross section being preferably somewhat less than the diameter of the pin at its largest portion. A slab 11 outon what is known as the slash grain or with its outer surface approximately parallel with what was originally the bark surface of the tree from, which it was cut is then glued to the outer face of each of the two core strips 10 and dowel pins 12 are driven obliquely through the upper and lower ends of the slabs 11 into the core strips 10 and are then glued so as to form in effect a dovetail connection between them since the upper pins extend downwardly and the lower pins extend upwardly as clearly seen in Fig. 2. The two core pieces with their respective slabs 11 are then braced at the opposite side edges so as to be parallel, and two other slabs 13 similar to the slabs 11 of slash grain are then glued to these opposite side edges of the partly assembled pin and are similarly bound in place by other dowel pins, one of the dowel pins of a slab entering each of the core pieces 10, as shown in Fig. 1, to not only hold the slabs to the core pieces, but to lock the core pieces together. The pin is then turned .to its proper shape with the center of the approximately rectangular core as its axis, the approximately oval shape of the body portion of the pin resulting in all four slabs being cut to an approximately oval shape as with the one shown in the front of the pin in Fig. 1. As the rectangular core has its diagonal somewhat smaller than the diameter of the finished pin there is a re- .sulting overlapping of the slabs 11 by the slabs 13 so that they form an unbroken belt surrounding the pin exposing the slash grain of the wood at all points.

The slabs as well as the core pieces are preferably made of maple thoroughly kiln dried so that the tenpin when completed is thoroughly kiln dried in the center as well as at the surface so that there is no further loss of moisture to vary its weight from the regulation weight to which it is adjusted at the time it is made or to distort its true symmetrical shape so as to aifect its stability as with pins turned from a single piece of stock. Furthermore the belt of slash cut slabs surrounding the pin assures a uniformity in effect produced upon the pin by a given blow irrespective. of the point on the pin at which the blow is struck.

That is to say, that the pin will always be:

struck uponits slash grain and will not therefore be affected by its position with relation to the direction of the blow as with a pin of a single piece of wood which is differently affected when struck on the edge grain side than when struck on the slash grain side. I

Incidentally the present construction results in a saving in the cost of manufacture,

for with the core portion only to be turned down to form the neck of the pin there is not much waste of stock nor as much, loss in time in turning it to shape as with a single-piece pin.- The thinner stock from which the present pin is made is also much less expensive than the heavy stock of a single-piece pin and permits of a more choice selection as to quality or grade of material -used. These economical features, however, are incidental to the greater features of advantage which have been pointed out, namely the permanent symmetry and weight of the pin with its resulting uniform stability and the freedom from splitting and uniform action due to the surrounding belt of slash grain material.

While the construction described is that which is preferred as having these desirable qualities to a superior degree, it may be somewhat departed from and still retain some of the desirable features, one of which modifications is shown in Fig. 4 wherein the core pieces 10 are made sufiiciently wide to form the diameter of the pin and have only the slabs 11 secured thereto by the dowel pins 12 which desirably extend deep enough into the pin to enter both of the core pieces 10'. Such a pin may be desirable in some instances as asomewhat cheaper construct-ion and with the grain of the core pieces 10 properly arranged may approximate the effect of the other construction in the qualifications mentioned.

A tenpin constructed in accordance with this invention has the true ring and action of a single-piece maple pin while being far more durable and permanent in its compliance with regulation specifications.

What I claim as new and desire to secure by Letters Patent is:

1. A tenpin, comprising a longitudinal central core and slabs secured to the opposite faces thereof.

2. A tenpin, comprising a longitudinal central core formed of a pair of core strips glued together, and slash grain slabs glued to the opposite faces of the core strips.

3. A tenpin, comprising a longitudinal central core formed of a pair of core strips glued together, and slash grain slabs glued to the opposite faces and edges of the core strips.

4. A tenpin, comprising aoentral longitusurrounding the tenpin, and oblique dowel 130 pins extending through the slabs and into theslab to the core and the dowel pins of the core in diiferent directions to lock the the slabs at. the edges of the strlps forming slabs in place. w the core entering both of such strips to lock 7. A tenpin, comprising a pair of strips of then! together.

5 maple glued together to form a central lon- In testimony whereof,I afiix my signature,

gitudinasllcolil'e approximilteslly'lsqualre crolss in presence of two witnesses, I section, as grain map e a s gue to t e four faces of the core, and dowel'pins pass- I EDGAR WILLSON' ing through the upper'and lower ends of the" Witnesses:

-10 slabs into the core, the dowel pins of each J.- I. Mnmemn,

slab extending at difierent'angles to lock Tnoms H. RYAN. 

